Publications
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The East African rift system in the light of KRISP 90 The East African rift system in the light of KRISP 90
On the basis of a test experiment in 1985 (KRISP 85) an integrated seismic-refraction/teleseismic survey (KRISP 90) was undertaken to study the deep structure beneath the Kenya rift down to depths of 100–150 km. This paper summarizes the highlights of KRISP 90 as reported in this volume and discusses their broad implications as well as the structure of the Kenya rift in the general...
Authors
Gordon R. Keller, C. Prodehl, J. Mechie, K. Fuchs, M.A. Khan, Peter K.H. Maguire, Walter D. Mooney, U. Achauer, P.M. Davis, R.P. Meyer, L.W. Braile, I.O. Nyambok, G. A. Thompson
Precursory swarms of long-period events at Redoubt Volcano (1989-1990), Alaska: Their origin and use as a forecasting tool Precursory swarms of long-period events at Redoubt Volcano (1989-1990), Alaska: Their origin and use as a forecasting tool
During the eruption of Redoubt Volcano from December 1989 through April 1990, the Alaska Volcano Observatory issued advance warnings of several tephra eruptions based on changes in seismic activity related to the occurrence of precursory swarms of long-period (LP) seismic events (dominant period of about 0.5 s). The initial eruption on December 14 occurred after 23 years of quiescence...
Authors
B. A. Chouet, R.A. Page, C.D. Stephens, J.C. Lahr, J.A. Power
Fluid expulsion sites on the Cascadia accretionary prism: mapping diagenetic deposits with processed GLORIA imagery Fluid expulsion sites on the Cascadia accretionary prism: mapping diagenetic deposits with processed GLORIA imagery
Point-discharge fluid expulsion on accretionary prisms is commonly indicated by diagenetic deposition of calcium carbonate cements and gas hydrates in near-surface (
Authors
Bobb Carson, Erol Seke, Valerie F. Paskevich, Mark L. Holmes
The Geology of Gaspra The Geology of Gaspra
The surface of Gaspra can be divided into several facets separated by ridges. Superimposed on the facets and ridges are two populations of craters. Type 1 craters are crisply defined and constitute a production function of impact origin. Type 2 craters are mostly irregular shallow depressions and probably of various origins. Some of the type 2 craters may have formed by impact and be...
Authors
M. H. Carr, Randolph L. Kirk, A. McEwen, J. Veverka, P. Thomas, J.W. Head, S. Murchie
Composition of the crust beneath the Kenya rift Composition of the crust beneath the Kenya rift
We infer the composition of the crust beneath and on the flanks of the Kenya rift based on a comparison of the KRISP-90 crustal velocity structure with laboratory measurements of compressional-wave velocities of rock samples from Kenya. The rock samples studied, which are representative of the major lithologies exposed in Kenya, include volcanic tuffs and flows (primarily basalts and...
Authors
Walter D. Mooney, N.I. Christensen
Measurements of heat and mass flow from thermal areas in Lassen Volcanic National Park, California, 1984-93 Measurements of heat and mass flow from thermal areas in Lassen Volcanic National Park, California, 1984-93
Rates of heat loss from eight steam-heated thermal areas and one conductively heated thermal area in Lassen Volcanic National Park have been determined from measurements made during the period 1984-93. Total heat discharge at the steam-heated areas is assumed proportional to the rate of steam upflow from underlying reservoirs. The dominant mode of heat loss differs among the areas...
Authors
Michael L. Sorey, Elizabeth M. Colvard
GPS measurements on the island of Hawaii in 1992 GPS measurements on the island of Hawaii in 1992
No abstract available.
Authors
Asta Miklius, E.Y. Iwatsubo, R.P. Denlinger, A.T. Okamura, M. K. Sako, K.M. Yamashita
Preparing for the next eruption in the Cascades Preparing for the next eruption in the Cascades
No abstract available.
Authors
J.W. Ewert, B.M. Myers, S.R. Brantley
Analysis of deep seismic reflection and other data from the southern Washington Cascades Analysis of deep seismic reflection and other data from the southern Washington Cascades
No abstract available.
Authors
W. D. Stanley, S. Y. Johnson, V. F. Nuccio
Preliminary map showing quaternary faults and landslides in the Cliff Lake 15' quadrangle, Madison County, Montana Preliminary map showing quaternary faults and landslides in the Cliff Lake 15' quadrangle, Madison County, Montana
No abstract available.
Authors
J.M. O’Neill, T. H. LeRoy, Paul E. Carrara
Campground talk and slide show on volcanoes for Chiricahua National Monument Campground talk and slide show on volcanoes for Chiricahua National Monument
The slides and the accompanying script presented here are based on a campground presentation at Chiricahua National Monument in 1994. Examples of eruptions at active volcanoes are used to help the audience visualize events that took place in the National Monument 27 million years ago. This presentation stresses the following themes: 1) The National Monument lies on the flank of an...
Authors
J.S. Pallister, E. A. Du Bray
A compilation of sulfur dioxide and carbon dioxide emission-rate data from Mount St. Helens during 1980-88 A compilation of sulfur dioxide and carbon dioxide emission-rate data from Mount St. Helens during 1980-88
Airborne monitoring of Mount St. Helens by the USGS began inMay 1980 for sulfur dioxide emissions and in July 1980 forcarbon dioxide emissions. A correlation spectrometer, orCOSPEC, was used to measure sulfur dioxide in Mount St.Helens' plume. The upward-looking COSPEC was mounted in afixed-wing aircraft and flown below and at right angles to theplume. Typically, three to six traverses...
Authors
Kenneth A. McGee, Thomas J. Casadevall